Moving-handrail device in moving stairways and the like

ABSTRACT

The moving handrail of endless-belt form of a moving stairway is driven at a part of its return span by a drive mechanism comprising, essentially, two floating carriages, friction-drive wheels rotatably mounted in a row on one of the carriages, idler wheels rotatably mounted in a row on the other carriage in positions confronting respective friction-drive wheels with the moving handrail interposed and clamped therebetween, and a cam mechanism reacting to increasing driving force on the handrail to cause the friction-drive wheels and idler wheels to grip the handrail with increasing force.

United States atent lwata 1 51 May 30, 1972 MOVING-HANDRAIL DEVIQE IN [56] Referenees Cited MOVING STAIRWAYS AND THE LIKE UNITED STATES PATENTS [72] Inventor: Tetjo lwata, Tokyo, Japan 3,414,109 12/1968 Clark 198/18 [73] Assignee: Tokyo Shibaura Denki Kabushlki Kaisha, FOREIGN PATENTS O APPLICATIONS a/k/a Tokyo Shibaura Electric Co., Ltd., Kawasaki shi Japan 1,086,930 10/1967 Great Britain ..198/16 R [22] Filed: Jan. 5, 1971 Primary Examiner-Richard E. Aegerter Assistant E.raminerDouglas D. Watts [21] Appl. No.. 104,109 ArmrneyRobert E. Burns and Emmanuel J Lobato 301 Foreign Application Priority Data [571 ABSTRACT Jan. 12, 1970 Japan... ..45/3816 handral. of endlessbelt form 9 3 is driven at a part of its return span by a dr1ve mechanism com- 1970 45/121349 prising, essentially, two floating carriages, friction-drive Dec. 5, 1970 Japan ..45/ 121350 wheels rotatably mounted in a row on one f the carriages idler wheels rotatably mounted in a row on the other carriage [52] U.S. Cl. ..198/16 R in positions confronting respective friction-drive wheels with [51] Int. Cl ..B66b 9/12 h ng h r interposed and clamped therebetween, 58 Field of Search ..198/16, 203; 74/226, 227 and a Cam mechanism reacting to increasing driving force on the handrail to cause the friction-drive wheels and idler wheels to grip the handrail with increasing force.

8 Claims, 13 Drawing Figures Patented May 30, 1972 3,666,075

6 Sheets-Sheet l Patented May 30, 1972 3,666,075

6 Sheets-Sheet 2 FIG. 3

FIG. 4

Patented May 30, 1972 6 Sheets-Sheet 3 FIG. 5

Patented May 30, 1972 3,666,075

6 Sheets-Sheet 4 Patented May 30, 1972 6 Sheets-Sheet 5 FIG. 9

FIG.

' Pat gnlted May 30, 1972 3,666,075

6 Sheets-Sheet 6 BACKGROUND OF THE INVENTION This invention relates generally to flexible belt-like structures and driving means therefor. More particularly, the invention relates to a new and advanced moving-handrail device in moving stairways (or escalators), moving sidewalks (or moving walkways), and like apparatuses, the handrail device being especially suitable for such apparatus of the so-called transparent balustrade type.

In known moving-handrail devices of this class, the handrail-driving mechanism is installed within the so-called truss or machine frame below the floor or stairway level and not in the end parts where the direction of travel of the handrail is reversed, the driving mechanism being of friction drive type. However, the handrail driving force tends to decrease because of stretching of the moving handrail due to changes therein with the passage of time and the resulting changes in the wraparound angles of the handrail and the frictional force thereof. As a counter measure, the common practice known heretofore has been to correct the relationship between the wraparound angles and frictional force by means such as weights and tension pulleys.

However, when curves, particularly recurves or curves in the reverse direction in the path of travel of the moving handrail are numerous, fatigue due to the material of the moving handrail itself is promoted. As a result, not only is the serviceable life of the handrail shortened, but the traveling resistance due to irregular friction resistance at the various curves increases, whereby the required driving torque increases. Moreover, the construction of the apparatus inevitably becomes complicated, and the assembly and organization thereof becomes troublesome.

Furthermore, the maintenance and checking of the entire moving way (e.g., escalator) become troublesome. Consequently, it has heretofore been difficult to obtain reliability in the smooth travel of the moving handrails, whereby vibration, noise, and other defective occurrences were caused. The ultimate result has been that fully satisfactory handrail devices could not be produced to sell at reasonably low prices.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above described difficulties without the use of weights and tension pulleys to correct the wrap-around angle of the moving handrail.

More specifically, an object of the invention to provide a moving handrail device in which the handrail is clamped firmly between and driven positively by two groups of wheels, one group being that of friction-drive wheels.

Another object of the invention is to provide, in the above described moving handrail device, a cam mechanism operating in reaction to increasing driving force imparted to the handrail, i.e., increasing load on the handrail, to cause the two groups of wheels to grip the handrail with increasing force thereby to prevent slippage and loss of driving force and power due to elongation of the moving handrail.

According to the present invention, briefly summarized, there is provided, in a moving stairway or the like apparatus of the class referred to above, a moving-handrail device comprising a moving handrail adapted to travel partly along a guide rail in the balustrade structure and partly in the frame therebelow, motive power means, and a driving mechanism disposed in the frame and operated by the motive power means to drive the moving handrail at its return span in the frame, the driving mechanism comprising, essentially, two floating carriages, friction-drive wheels rotatably mounted in a row on one of the carriages and driven by the motive power means, idler wheels rotatably mounted in a row on the other carriage in positions confronting respective friction-drive wheels with the moving handrail interposed and clamped therebetween, and a cam mechanism operating in reaction to increasing driving force imparted to the handrail to cause the friction-drive wheels and idler wheels to grip the handrail with increasing force.

The nature, principle, details, and utility of this invention will be more clearly apparent from the following detailed description with respect to examples of preferred embodiment of the invention when read in conjunction with the accompanying drawings, in which like parts are designated by like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a fragmentary side elevation showing the upper part of an escalator in which an example of a handrail device according to the invention is installed;

FIG. 2 is an enlarged side elevation of one part of the moving handrail device shown in FIG. 1;

FIG. 3 is a simplified side view for the purpose of describing the operation of the device shown in FIG. 2;

FIG. 4 is a fragmentary, diagrammatic side view for the purpose of describing force relationships at the time of operation when the moving handrail is driven in the direction opposite to that indicated in FIG. 3;

FIG. 5 is a fragmentary side elevation, similar to FIG. 1, showing another example of the moving handrail device according to the invention;

FIG. 6 is an enlarged side view showing one part of the handrail device shown in FIG. 5;

FIG. 7 is a diagrammatic side view indicating force relationships in the device illustrated in FIG. 5 when the device is operating in one driving direction;

FIG. 8 is a diagrammatic side view indicating force relationships in the same device operating in the opposite driving direction;

FIG. 9 is a side view showing another example, which is a modification of the device shown in FIG. 6, of the invention;

FIG. 10 is a fragmentary side elevation, similar to FIG. 1, illustrating still another example of the invention;

FIG. 11 is an enlarged side view showing one part of the moving handrail device shown in FIG. 10;

FIG. 12 is a sectional view taken in the plane indicated by line XII-XII in FIG. 11 as viewed in the arrow direction; and

FIG. 13 is a sectional view taken in the plane indicated by line XIIIXIII in FIG. 11 as viewed in the arrow direction.

DETAILED DESCRIPTION Referring first to FIG. 1, reference numeral 1 designates a support frame of known type of an escalator. As is well known in the art, the support frame 1 comprises an upper horizontal extension (shown), a lower horizontal extension (not shown) and a sloping intermediate extension or truss 2 partly shown in FIG. 1. Above and along the support frame there are disposed a pair of balustrades 4 having struts 3, one of the balustrades being shown in FIG. 1.

Each of the balustrades 4 has a guide rail 4a disposed along the outer edge of the balustrade and an endless moving handrail travels along the guide rail 4a. The lower or return run of the hand belt 5 passes through the interior space of the truss 2.

Within the truss 2, there are provided a pair of opposing upper and lower guide bases 6 and 7 which are rigidly secured to the truss 2. The inner surface of the upper guide base 6 is provided with cam surfaces 6a formed as shown in FIG. 2.

A pair of floating carriages 8 and 9 are interposed between the guide bases 6 and .7. These floating carriages 8 and 9 are coupled to each other by means of pins 10 fixed to the carriage 8 and slots 11 in the carriage 9, the pins 10 slidably engaging respective slots 11. It will be noted that the carriages 8 and 9 are movable toward and away from each other in a direction transverse to the run of the moving handrail 5 passing through the truss 2.

A series of friction-drive wheels 12a, 12b, 12c, and 12d are rotatably supported on shafts 13a, 13b, 13c, and 13d, respectively, which are in turn mounted on the carriage 8 and support sprockets 14a, 14b, 14c, and 14d the shafts being parallel and spaced apart and being alined transversely relative to the handrail. These sprockets 14a, 14b, 14c, and 14d are adapted to be driven in the same direction through chains 15 drivingly connecting adjacent pairs of the sprockets. All of the frictiondrive wheels 12a, 12b, 12c, and 12d are in contact with one surface of the handrail 5.

The floating carriage 9 has a series of idler wheels 16a, 16b, 16c, and 16d rotatably supported by parallel and spaced apart support shafts 17a, 17b, 17c, and 17d, respectively, which are also aligned transversely. These idler wheels 16a, 16b, 16c, and 16d are in opposing or confronting relation to the frictiondrive wheels 12a, 12b, 12c, and 12d, respectively, and cooperate with the latter to grip the handrail 5 therebetween. The floating carriage 9 also has a pair of guide rollers 9a and 9b which roll on the surface of the guide base 7 for guiding the carriage 9 along the base 7. It is to be noted that there are slight clearances between the guide base 7 and the idler wheels 16a, 16b, 16c, and 16d.

On the upper edge of the floating carriage 8 are rotatably supported a pair of rollers 18, the peripheral surfaces of which are in engagement with the cam surfaces 6a on the guide base 6. It is to be noted that because of the engagement of the rollers 18 with the notch-shaped cam surfaces 6a, the pair of the floating carriages 8 and 9 are prevented from moving downward along the inclined truss 2.

Referring back to FIG. 1, a motor 19 is provided in the horizontal extension of the support frame 1, and is coupled to a speed-reduction device 20, the output shaft 20a of which is drivingly coupled to a pulley 22 through a belt 21. A sprocket 23 has a shaft common to that of the pulley 22 and is, therefore, driven by the pulley 22. An endless chain 24 is passed around the sprocket 23 and a sprocket (not shown) coaxial with the sprocket 14a.

The moving handrail device of the above described organization operates in the following manner. It will be apparent that when the motor 19 is operated, the sprocket 14a is also driven at a reduced speed through the above mentioned power transmission mechanism, and the other sprockets 14b, 14c. and 14d are also driven in the same direction through the chains 15.

It will be assumed that the sprockets 14a, 14b, 14c, and 14d and, therefore, the friction-drive wheels 12a, 12b, 12c, and 12d are driven counter-clockwise as viewed in FIG. 2. In this case, the opposing pairs of the friction-drive wheels 12a, 12b, 12c, and 12d and the idler wheels 16a, 16b, 16c, and 16d cooperate to drive the handrail 5 upwards as shown by an arrow in FIG. 2. Then, reaction causes the floating carriages 8 and 9 to move downward and leftward with the result that the follower rollers 18 move from an intermediate position in the notch-shaped cam 6a to a leftwardly or downwardly displaced position as shown in FIG. 2.

Referring to FIG. 3 showing a simplified construction of the driving mechanism shown in FIG. 2, the mechanical relationship between the cam surfaces 6a and the follower rollers 18 will now be explained.

In order to create a driving force P on the handrail 5 by the rotation of the friction-drive wheels, the follower rollers 18 must bear against the cam surfaces 6a with forces P and P These forces will be divided into component forces P and P parallel to the running direction of the handrail 5 and component forces P and I normal to the direction of the handrail 5. The sum of P 1'" is equal to P It will be apparent that component forces P and P are opposed by reaction forces from the cam surfaces 6a. These reaction forces cause the friction-drive Wheels 120 and 12d to be pressed against the surface of the handrail to create frictions between the friction-drive wheels and the handrail.

When the load on the escalator, or, more precisely, on the handrail 5, is increased or decreased, the driving force P is also increased or decreased, respectively. It will be noted that when the driving force P become greater, the follower rollers 18 are displaced leftward and downward as viewed in FIG. 3 to press the friction-drive wheels against the surface of the handrail 5 with increased forces and vice versa. Therefore, the hand belt driving mechanism according to the invention imparts suitable gripping forces to the handrail in proportion to the driving force P This prevents undue stress in the hand belt and ensures prolonged life of the belt.

The angle 6 formed between the surface of the guide base 6 and the surface of the cam 60 should be selected so as to provide the best operating condition of the handrail driving mechanism.

FIG. 4 illustrates the relation between the follower roller and the cam in the case Where the handrail 5 is driven in reverse direction. It will be apparent that when the belt 5 is reversely driven, each follower roller 18 engages the opposite face ofthe cam 6a.

FIG. 5 through 8, inclusive, show another example of the invention. In these figures, the same reference numerals as are used in FIGS. 1 and 2 designate the same or corresponding members and parts.

The truss 2 is again provided with a pair of parallel guide bases 6 and 7. It is to be noted, however, that the base 6 is located at a lower position and the base 7 is located at an upper position. The lower base 6 has an upper edge formed with a pair of the notch-shaped cams 6a.

Between the guide bases 6 and 7, there are disposed a pair of floating carriages 8 and 9 which are connected with each other by means of slots 111 and pins engaging the slots.

and are movable toward and away from each other.

The carriage 8 supports a series of friction-drive wheels 112a, 112b, l12c, and 112d, which. are rotatable about support shafts l13a,113b, 113C, and 113d carried by the carriage 8. The support shafts 1 13a, 1 13b, 113C, and 113d also support sprockets 114a, 114b, 114e, and 114d.

The adjacent sprockets 114a and 114b, and 1140 and 114d are drivingly coupled to each other through endless chains 115 and adapted to be driven in the same direction. All of the friction-drive wheels 112a, 112b, 1120, and 112d engage the upper surface of the handrail 5.

The carriage 9 supports a series of support shafts 117a, 117b, 117s, and 117d on which a series of idler wheels 116a, 116b, 1160, and 116d are rotatably mounted, respectively. These idler wheels are in opposed relation to respective friction-drive wheels and cooperate with the latter to grip the hand belt 5 therebetween.

On the outer edge of the carriage 8 there are rotatably mounted guide rollers 118C and 118d which roll on the surface of the guide base 7. Furthermore, the carriage 9 is provided with follower rollers 1 18a and 118b rotatably mounted on the outer edge of the carriage 9. These follower rollers 118a and ll8b are in engagement with the cam surfaces 6a. It is to be noted that there are slight clearances between the surface of the guide base 6 and the peripheral surfaces of the idler rollers 116a, 116b, 116a, and 116d. Because ofthe engagement of the follower rollers 118a and 1 18b with the cam 6a, the carriages 8 and 9 are prevented from moving downward along the length of the inclined truss 2.

Sprockets 119a and 119b are rigidly mounted on the support shafts 113b and 113C and an endless intermediate transmission chain 120 is passed around both the sprockets 119a and 11912 and around guide rollers 121a, 121b, 121C, and 121d and the sprocket 23. The sprocket 23 is driven by power from the motor 19 as in the case of FIGS. 1 and 2.

In operation, the motor 19 is operated to drive the sprocket 23 which, in turn, drives the sprockets 119a and 1 19b through the chain 120. Thus, all of the friction-drive wheels 112a, 112b, 1120, and 112d are turned to drive the handrail 5, cooperating with the associated idler rollers 116a, 116b, 1160, and 116d.

The operative relationship between the cams 6a and the follower rollers 118a and l18b is identical to that explained with reference to FIGS. 1 through 4 is indicated in FIGS.7 and 8. In these figures the cam 6a and the roller 118b are shown in inverted positions for the purpose of comparison with FIG. 3. It will be apparent that the operation of the handrail driving mechanism shown in FIGS. 5 and 6 is almost identical to that of the handrail driving mechanism shown in FIGS. 1 and 2.

FIG. 9 illustrates a modification of the driving mechanism shown in FIG. 6. The mechanism shown in FIG. 9 differs from that shown in FIG. 6 in that the friction-drive wheels 1 12a and 112d and the cooperating idler rollers 116a and 116d are omitted to make the structure smaller.

The handrail driving mechanisms shown in FIGS. 5 through 9 are advantageous in that, because the angular extent of the intermediate transmission chain 120 around each of the sprockets 119a and 1I9b is reduced as compared with the angular extent of the chain 24 around the sprocket on the support shaft 13a, the curving extent of the chain 120 is made smaller, so that excessive curving of the chain 120 can be avoided. Another advantageous feature is that the transmission of force from the chain 120 to the friction-drive wheels is reliable since the chain 120 passes around two sprockets 119a and ll9b. v

In FIGS. through 13, inclusive, there is illustrated a further example of the invention. In these figures, the same reference numerals as are used in FIGS. 5 and 6 designate the same or like members and parts.

Also in this example, pins 210 on a floating carriage 8 are in engagement with slots 21 1 cut in a floating carriage 9 so as to allow relative movement of the carriages 8 and 9 toward and away from each other.

The carriage 8 supports support shafts 213a, 213b, 213a, 213d, and 213a on which friction-drive wheels 212a, 212b, 212e, 212d, and 2122 are rotatable. The support shafts also carry thereon a series of sprockets 214a, 2140, 214d, and

. 2I4e. Between adjacent sprockets and on the carriage 8 there are rotatably mounted a series of idler sprockets 215a, 215b, 2150, and 215d, and an endless intermediate transmission chain 220 passes around all of the sprockets 214a, 214e and all of the idler sprockets 215a, 215e in a zig-zag fashion. The chain 220 further passes around idler sprockets 221a, 221b, and 2210 and engages the driving sprocket 23 driven by power from the motor 19. The friction-drive wheels are all in frictional engagement with the upper surface of the handrail 5.

Idler wheels 216a, 216b, 2166, 216d, and 216e are rotatably mounted on the floating carriage 9 cooperate with the friction-drive wheels 2120, 212:; to grip the handrail belt 5 therebetween.

The carriage 9 has a pair of cam follower rollers 218a and 21812 which cooperate with cam surfaces 6a of the guide base 6 in the same manner as described hereinbefore with reference to FIGS. 1 through 9. The carriage 8 has mounted thereon a pair of guide rollers 2180 and 218d which engage the surface of the guide base 7.

When the motor 19 is operated, the sprocket 23 is rotated and drives the sprockets 214a, 214b, 214e in unison via the chain 220, whereby the friction-drive wheels 212a, 212b, 2l2e are driven and cooperate with the idler wheels 216a, 216b, 216e to advance the handrail 5. The relation of the cams 6a and the follower rollers 218a and 218b is exactly the same as that described hereinbefore.

The handrail driving mechanism shown in FIGS. 10 through 13 is advantageous in that a more powerful and reliable drive of the friction-drive wheels can be obtained since a single chain 220 passes around all of the sprockets for the frictiondrive wheels in a zig-zag fashion.

I claim:

1. In a moving stairway, moving walkway, or the like having a balustrade structure provided with a guide rail and a frame structure disposed below the balustrade structure, a movinghandrail device comprising a moving handrail of flexible beltlike form adapted to travel longitudinally partly along the guide rail and partly in the frame structure, motive-power means for supplying power to drive the moving handrail, and a driving mechanism disposed in the frame structure and operated by said power to impart traveling motion to the moving handrail, said driving mechanism comprising:

first and second guide members fixed to the frame structure on respectively opposite sides of and spaced apart from the moving handrail;

one of said guide members having at least one cam surface;

a first floating carriage interposed between one of the guide members and the handrail and having at least one follower member engaged with said cam surface;

a second floating carriage interposed between the other guide member and the handrail and guided by said other guide member;

coupling means for coupling the first and second floating carriages in a manner to permit relative movement thereof toward and away from each other;

a plurality of idler wheels rotatably supported on one of the floating carriages and rollably contacting one side of the handrail;

a plurality of friction-drive wheels rotatably supported on the other floating carriage in reliable and frictional contact with the other side of the handrail and coupled with the motive power means to be driven thereby and thereby to drive the handrail;

a reaction force thereby being produced to cause the follower member to follow the cam surface and thereby to cause the handrail to be gripped firmly by the friction drive wheels and the idler wheels with a force which increases with increasing drive force imparted to the handrail.

2. A moving-handrail device according to claim 1 in which the cam surface is a triangular cutout formed in an edge part of the guide member.

3. A moving-handrail device according to claim 1 in which the follower member is a follower roller rotatably supported on the first floating carriage.

4. A moving-handrail device according to claim 1 in which at least two guide rollers are rollably interposed between the second floating carriage and the guide member for guiding the same.

5. A moving-handrail device according to claim 1 in which the coupling means comprises at least one slot formed in one of the floating carriages and at least one pin fixed to the other floating carriage and slidably engaged with the slot.

6. A moving-handrail device according to claim I in which the motive power means comprises a prime mover producing said power, a driving chain for transmitting said power to a central shaft of one of the friction-drive wheels, and other driving chains for transmitting power from said shaft to similar shafts of other friction-drive wheels successively from one wheel to the adjacently next wheel.

7. A moving-handrail device according to claim 1 in which the motive power means comprises a prime mover producing said power, a driving chain for transmitting said power to central shafts of one pair of adjacent wheels among the frictiondrive wheels and other driving chains for coupling said pair of adjacent wheels to adjacent other friction-drive wheels.

8. A moving-handrail device according to claim 1 in which the motive power means comprises a prime mover, idler wheels each interposed between and apart from each pair of adjacent friction-drive wheels, and a driving chain for coupling the prime mover and all friction-drive wheels, said chain being passed around a driving wheel of the prime mover and alternately around sprockets on all friction-drive wheels and the idler wheels in succession in a zig-zag path. 

1. In a moving stairway, moving walkway, or the like having a balustrade structure provided with a guide rail and a frame structure disposed below the balustrade structure, a movinghandrail device comprising a moving handrail of flexible beltlike form adapted to travel longitudinally partly along the guide rail and partly in the frame structure, motive-power means for supplying power to drive the moving handrail, and a driving mechanism disposed in the frame structure and operated by said power to impart traveling motion to the moving handrail, said driving mechanism comprising: first and second guide members fixed to the frame structure on respectively opposite sides of and spaced apart from the moving handrail; one of said guide members having at least one cam surface; a first floating carriage interposed between one of the guide members and the handrail and having at least one follower member engaged with said cam surface; a second floating carriage interposed between the other guide member and the handrail and guided by said other guide member; coupling means for coupling the first and second floating carriages in a manner to permit relative movement thereof toward and away from each other; a plurality of idler wheels rotatably supported on one of the floating carriages and rollably contacting one side of the handrail; a plurality of friction-drive wheels rotatably supported on the other floating carriage in rollable and frictional contact with the other side of the handrail and coupled with the motive power means to be driven thereby and thereby to drive the handrail; a reaction force thereby being produced to cause the follower member to follow the cam surface and thereby to cause the handrail to be gripped firmly by the friction-dRive wheels and the idler wheels with a force which increases with increasing drive force imparted to the handrail.
 2. A moving-handrail device according to claim 1 in which the cam surface is a triangular cutout formed in an edge part of the guide member.
 3. A moving-handrail device according to claim 1 in which the follower member is a follower roller rotatably supported on the first floating carriage.
 4. A moving-handrail device according to claim 1 in which at least two guide rollers are rollably interposed between the second floating carriage and the guide member for guiding the same.
 5. A moving-handrail device according to claim 1 in which the coupling means comprises at least one slot formed in one of the floating carriages and at least one pin fixed to the other floating carriage and slidably engaged with the slot.
 6. A moving-handrail device according to claim 1 in which the motive power means comprises a prime mover producing said power, a driving chain for transmitting said power to a central shaft of one of the friction-drive wheels, and other driving chains for transmitting power from said shaft to similar shafts of other friction-drive wheels successively from one wheel to the adjacently next wheel.
 7. A moving-handrail device according to claim 1 in which the motive power means comprises a prime mover producing said power, a driving chain for transmitting said power to central shafts of one pair of adjacent wheels among the friction-drive wheels and other driving chains for coupling said pair of adjacent wheels to adjacent other friction-drive wheels.
 8. A moving-handrail device according to claim 1 in which the motive power means comprises a prime mover, idler wheels each interposed between and apart from each pair of adjacent friction-drive wheels, and a driving chain for coupling the prime mover and all friction-drive wheels, said chain being passed around a driving wheel of the prime mover and alternately around sprockets on all friction-drive wheels and the idler wheels in succession in a zig-zag path. 